Natural resources: Possibilities and dangers

The Kachimayu River Valley shows a wide diversity in its flora which adapted to the three ecological levels: the very humid sub-alpine, sub-tropical wasteland higher than 3'900 m.a.s.l., the humid, mountainous, sub-tropical forest between 3'900 and 3'500 m.a.s.l. and the dry moun-tainous low sub-tropical forest between 3'500 and 3'350 m.a.s.l. (IIUR; 1995). Pukllasunchis conducted an inicial investigation in colla-boration with the Institute of Ecology and Medical and Aromatical Plants (Instituto de EcologÌa y de Plantas Medicinales y Aromaticas IEPLAM) between January and June of 1998. About 190 different species have been iden-tified by their Latin, Quechua and Spanish names and regi-stered with photos. About 45 of these plants are known traditionally as medical remedies for all kinds of diseases and another 5 flowers are handed down as ornamental or mythical plants of the Inca era. Nowadays the local population is slowly losing its traditional knowledge of these plants as a result of the increasing influence of modern medicine in all the regions of Peru.

Fig. 9: Salvia opositiflora (Quech.: Ñuqchu): A very rare pink mutation of the originally red species. In the Inca society it was used as ornament for the mummies.

Fig. 10: Xantium spinosum (Quech.: Allqo kisqa): Tea made from the leaves cures renal infections, the roots have contraceptive effects when consumed at the 21st day of the menstrual cycle.

Many of these species specially adapted to specific ecological conditions are easily overpowered by stronger, more quickly expanding species (pio-neer vegetation). The main reason for this is overuse of the soil through extensive cattle, sheep and goat breeding. Based on the inquiry conduc-ted by Pukllasunchis (Erzinger; 2000), there are an estimated 290 lamas and 10 alpacas as native species, and 530 cows, 1'800 sheep, 130 goats and 300 pigs as introduced species that in the relatively small area of the rural zone. In comparison with the two native species of domestic animals, the four hoofed foreign animals have a much larger ecological impact on the vegetation. One reason for this is that they are incapable of biting off the grass because they have only one row of teeth. The other reason for their negative impact is the destructive influence on the soil of their hooves. Besides these physical effects the enormous number of animals that are grazed in a very limited area impacts nega-tively on the chemical composition of the soil through their defecation.

Extensive farming of mainly nutrition-extractive species like maize and potatoes makes another grave negative impact on the fertility of the soil. Most of this farming takes place in very steep terrain that is exposed to the erosion impact of the heavy summer rains. Many fields are harvested two times per year - first potatoes, later in the season maize - and some are even used for a third time to graze the herds during the dry winter season. The mixed cultivation of these crops together with native legu-minous plants (Leguminosae sp.) is known of but very rarely applied, probably as a consequence of lack of demand. This extreme over-use of the ground leads to a progressive erosion of the fertile soil which in turn results in an expansion of the terrain used for agricultural purposes.

An additional problem for the nutrition equilibrium is the enormous loss of water caused by the loss of native woodland. Studies in the classification of eco-zones in this region have showed that according to the existing microclimates at least 45% of the whole area there should be covered by wood, the appropriate percentage of terrain used for pure agriculture is estimated at about 5% and about 35% for pastureland (IIUR; 1995). In reality not more than 5% of the Kachimayu River Valley are covered by wood, mainly due to recent reforestation through introduced species such as Eucalyptus (Eucaliptus globulus). The loss of protection against the strong sun radiation and the raised water consumption of the Eucalyptus both contribute to the increasing decomposition and as a consequence to the progressive erosion of the fertile soil.

Fig. 11: Polylepis incana (Quech.: Q'euña): The only native tree that still exists in small woods on the banks of the River Kachimayu.

Fig. 12: Escallonia resinosa (Quech.: Chachacomo): Another native tree whose incidence across the whole region is very rare not to be found in woods anymore.

The destruction of a number of different micro-ecosystems, belonging mainly to woodland or meagre grassland eco-systems, is resulting increasingly in a loss of bio-diversity in the local flora. The disappearance of these habitats results in indirect negative effects on the bio-diversity of the fauna, of insects and birds in particular, but also of reptiles and small mammals. The whole equilibrium of the system has shifted and the wide variety of specially-adapted species have been replaced by more gene-rally-adaptable species. A new ecological equilibrium such as this is often less buffered against exterior physical impacts and therefore much less stable and less auto-controlling. The eventual consequence of the disturbance of such a delicate equilibrium may be a mayor ecological collapse.

Fig. 13: Anchotatus peruvianus (Quech.: K'aspi kuru): The stick insect depends on uncultivated grassland.

Fig. 14: Nycticorax nycticorax (Quech.: Huachua): The heron suffers from the disappearance of healthy humid biotopes and of safe breeding-places.

Another challenging ecological problem is the organic overload of the water (eutrofication) by human and animal excrement and detergents. Both the river and the open water pipes are often so highly polluted that already in the first community of the current the drinking water can not be consumed uncooked. This situation results in high external costs for all the communities in the valley and also has a strong negative impact on the aquatic ecosystems and, in consequence, on the survival of certain aquatic insects and amphibians. These animals depend directly on the purity and quality of the water. The organic overload can provoke an explosive reproduction of certain organotrophic aquatic microorganisms, while the toxic detergents reduce the survival possibilities of the more sensitive aquatic animals. On an indirect level, the state of aquatic systems also affects the numbers of many birds and reptiles that hunt these aquatic insects and amphibians.

Fig. 15: Aeshna sp. (Quech.: Karta karta): The dragon-fly, as an aquatic insect, depends directly on the purity of aquatic systems.

Fig. 16: Vanellus resplendens (Quech.: Lique lique): This water bird depends indirectly on the abundance of its aquatic nourishment.

 

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